module.exports = (totalSize, req, res) => {
	const range = req.headers['range'];
	if (!range) {
		return { code: 200 }
	}
	const sizes = range.match(/bytes=(\d*)-(\d*)/);
	const end = sizes[2] || totalSize-1;
	const start = sizes[1] || totalSize - end;

	if(start > end || start <0 || end > totalSize) {
		return {code :200}
	}

	res.setHeader('Accept-Ranges', 'bytes');
	res.setHeader('Content-Range', `bytes ${start}-${end}/${totalSize}`);
	res.setHeader('Content-Length', end - start);

	return {
		code: 206,
		start: parseInt(start),
		end: parseInt(end)
	}
}
